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How to get ID of the last updated row in MySQL?
...T 1;
SELECT @update_id;
EDIT by aefxx
This technique can be further expanded to retrieve the ID of every row affected by an update statement:
SET @uids := null;
UPDATE footable
SET foo = 'bar'
WHERE fooid > 5
AND ( SELECT @uids := CONCAT_WS(',', fooid, @uids) );
SELECT @uids;
This w...
Why is argc not a constant?
...this case, history is a factor. C defined these inputs as "not constant", and compatibility with (a good portion of) existing C code was an early goal of C++.
Some UNIX APIs, such as getopt, actually do manipulate argv[], so it can't be made const for that reason also.
(Aside: Interestingly, al...
How do I execute a stored procedure once for each row returned by query?
...stored procedure that alters user data in a certain way. I pass it user_id and it does it's thing. I want to run a query on a table and then for each user_id I find run the stored procedure once on that user_id
...
Comparing Dates in Oracle SQL
...C, doesn't necessarily mean December. It depends on your NLS_DATE_LANGUAGE and NLS_DATE_FORMAT settings. To ensure that your comparison with work in any locale you can use the datetime format model MM instead
The year '95 is inexact. You know you mean 1995, but what if it was '50, is that 1950 or 2...
Simple explanation of clojure protocols
I'm trying to understand clojure protocols and what problem they are supposed to solve. Does anyone have a clear explanation of the whats and whys of clojure protocols?
...
What is stability in sorting algorithms and why is it important?
...ms are stable by nature like Insertion sort, Merge Sort, Bubble Sort, etc. And some sorting algorithms are not, like Heap Sort, Quick Sort, etc.
Background: a "stable" sorting algorithm keeps the items with the same sorting key in order. Suppose we have a list of 5-letter words:
peach
straw
appl...
PHP and MySQL - how to avoid password in source code? [duplicate]
...configuration file.
Many frameworks use this (Zend, CakePHP, Kohana, etc) and it's the most common way of doing things (even in a non-PHP environment such as ASP.NET with its web.config files). This allows you also to copy over configuration values from environment to environment by just copying th...
MySQL Error 1215: Cannot add foreign key constraint
...
I'm guessing that Clients.Case_Number and/or Staff.Emp_ID are not exactly the same data type as Clients_has_Staff.Clients_Case_Number and Clients_has_Staff.Staff_Emp_ID.
Perhaps the columns in the parent tables are INT UNSIGNED?
They need to be exactly the same...
Is JavaScript an untyped language?
... talked about in one of the above answers - the runtime doesn't tag values and just treats each value as bits. JavaScript does tag values and has different behaviour based on those tags. So JavaScript obviously doesn't fit this category.
The other definition is from Programming Language Theory (the ...
Is there a REAL performance difference between INT and VARCHAR primary keys?
...AR as the primary key for reference lists (think US States, Country Codes) and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables.
...